Malicious PDF — malware analysis report

Static analysis result for SHA-256 51dcf3ff1d168239…

MALICIOUS

PDF

88.9 KB Created: 2021-03-26 07:06:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: f26f1cddd96003f0375761d5ba2099aa SHA-1: ea21aea3c3d6ecf3d6e3cfa8193eb601ef176eb6 SHA-256: 51dcf3ff1d16823944f41fdf5359b17147611747caadaaf201771093d9dec416
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, identified as a 'PDF_SEO_LINK_FARM' heuristic, suggesting it's designed to drive traffic to various sites. Several of these URLs point to domains known for hosting potentially unwanted or malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://jacksth.ru/award?keyword=ielts+speaking+cue+cards+2020+with+possible+answers+pdf+download PDF link annotation
    • https://cdn.sqhk.co/girasufu/YszjeAv/b._o._t._a_tarot_deck_download.pdfIn PDF document text
    • https://cdn.sqhk.co/zodavujera/hiBAjdy/math_kids_add_subtract_count_and_learn.pdfIn PDF document text
    • https://cdn.sqhk.co/zinoliwomi/f0HxieV/fetexixiredizirobot.pdfIn PDF document text
    • https://cdn.sqhk.co/jogowijalaro/iajgiil/ludo_3d_multiplayer_mod_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/kavejufa/Lidjgd2/prop_hunt_map_codes.pdfIn PDF document text
    • https://cdn.sqhk.co/famagafe/geYgjjc/75440880609.pdfIn PDF document text
    • https://cdn.sqhk.co/zomuzuta/cjbheje/wutakufevivakurebugojab.pdfIn PDF document text
    • https://cdn.sqhk.co/puvubuzu/alhj4jf/football_stickers_for_whatsapp_2020_swaps.pdfIn PDF document text
    • https://cdn.sqhk.co/xiwasazafu/njhbhdW/wupavutijikogubuziko.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/muvazi/53506595861.pdfIn PDF document text
    • https://s3.amazonaws.com/wazotojemov/nikon_d5100_twin_lens_kit_price.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3ee354ca-18ad-4028-ae6d-b11d36227c90/doriwexinesoj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/69026fbf-d89f-48cd-b2b0-d641a30405d6/57401422859.pdfIn PDF document text
    • https://s3.amazonaws.com/xutomoxu/saxofeg.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c291b228-cfae-412e-9058-891e62e95df7/rudutuziwomaperabijug.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b60d7af0-85e8-4c45-bd46-e68bdd836470/79975032868.pdfIn PDF document text
    • https://s3.amazonaws.com/wovigebi/57475784027.pdfIn PDF document text
    • https://dae57379-2785-4108-a223-4562ecbfc22e.filesusr.com/ugd/87ad98_a65927164eeb4fe890fa2f9b89a31600.pdf?index=trueIn PDF document text
    • https://cb47f074-0476-4434-b381-5672a365cab8.filesusr.com/ugd/c46c8a_a398f72b2fc843d69d9b50cb4c3eedd1.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/muvevanepen/peton.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6a4e9934-66d7-46b6-860c-58b78f019184/87897088249.pdfIn PDF document text
    • https://b03e51a8-7171-48c0-94d6-e4c032e6f37f.filesusr.com/ugd/9421c8_9005ab2a2a90415fab16e1967870e6f5.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f60f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF60F 6744 bytes
SHA-256: 0eac1552a6a0cc8d6d43e14f5c157d052ff2bf21460314f67a2c213e0a454e63
font_01_sfnt_off000106f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F6 5924 bytes
SHA-256: bd575dc6387c2dcfee0abaa823d816bc1cb9b1b1919b8c876d30b23eb76aa3ca
font_02_sfnt_off00011b29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B29 10628 bytes
SHA-256: 6e46a167ede3be85e7ebb44cf0eb0195fa46e234851849bd44e2e182c82ce55a
font_03_sfnt_off00013f9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F9A 16160 bytes
SHA-256: ab862ddcc36e5f8abbcc0ec12f45ee2a0a0017beba85073a80867d3ee452b16b